In a known vehicle seat, the seat cushion of the seat is formed with a cushion recess in an upper surface thereof, and a cushion member is fitted into this cushion recess in a vertically reversible manner. The rear side of the cushion member is formed with a receiving recess configured to receive a beverage container while the front side of the cushion member is flush with the remaining part of the upper surface of the seat cushion so that the cushion member may be used for retaining a beverage container when the rear side of the cushion member faces upward, and may define a part of the upper surface of the seat cushion when the front side of the cushion member faces upward. See JPH8-127279A, for instance.
In this arrangement, since the cushion member is fitted into the seat cushion which is soft and readily deformable, the beverage container may not be supported in a stable manner.